Magnetic regulator for audiphone-receivers.



o. E. WILLIAMS. 4 MAGNETIC REGULATOR FOB, AUDIPHONE REGEIVBRS.

APPLICATION FILED JAN. 4, 1908.

2, w 1 U M. /w .w j P.

m O 5 5 6. m 3 9 621ml@ @E 22?/5;

`(M-TABLES E/WILILIQAMS, OF NATIGK,,MASSAGHUSETTS.

-MAGNETIC RGULATORFOR AUDIPHONE-RECEIVERS.

Specification of Letters Patent. Patnted Oct., 12, 1909.

Application led January 4, '1908. Serial No. 409,265.

To all whom it may concern.'

Be it known that I, CHARLES. E. l/VIL- LrAMs, a citizen of the United States, residing at Natick, in the county of Middlesex andState of Massachusetts, have invented an Improvement in Magnetic Regulatorsfor Audiphone-Receivers, of which the following description, in connection with the accompanying drawings, is a-specication, like numerals on the drawings representing like parts.

One deaf Vperson can hear through a receiver more readily than another, and it often happens that the same deaf person will hear more sensitively in the morning than in the afternoon, and likewise the humidity and other conditions of the atmosphere vary the sensitiveness of receivers, which are also subject to a multitude of other iniiuences and conditions which render it advisable to control or regulate the amount of edective lines offorce of the electromagnet, and accordingly my present invention consists in providing means externally operable for controlling the amgount of effective flux passing throughthe' diaphragm Aand cores of the electromagnet when energized by a given current, and, believing this to be broadly new, I intend herein to claim the same commensurately.

In the drawings, in which I have shown a preferred embodiment of the invention, Figure 1 is a top plan view of one form of receiver', the cover and diaphragm lbeing omitted to disclose to better advantage my mechanism, Fig. 2 is a sectional View thereof, showing the parts more clearly; Fig. 3 is a cross-sectional detail of the regulating device; Figs. 4 and 5 are views similarv to Figs. 2 and 3 of a modified construction; and Figs. 6 and 7 arefragmentary sectional details of a further modification.

The particular form of receiver herein illustrated forms the subject matter of another application, and I therefore omit a description of the details thereof, it being suficient for the purpose of the present application to mount the electromagnet in any suitable receiver case 1 provided with a cap or cover 2, diaphragm 3 and magnet cores 4, 5, supporting usual spools or windings 6.

The construction Vthus far described may be of any usual kind in which the windings 6 of the electromagnet providethe requisite magnetic field orlines of force at the upper end of the cores 4, 5, adjacent the diaphragm 3. Accordingly to vary the effectiveness of these lines of force or regulate the flux from one pole or core-end to the other, I provide a soft iron slide or reciprocating device, shown 1n Figs. l, 2 and 3 as a screw 7 threaded snugly at 8 in the core 5 1n order to preventany undue air gap or space at the point 8 and in order to afford as complete a closed magnetic path for the 4flux as possible, said screw being externally operable by any suitable means as, by a milled nut 9 mounted to swivel or turn at 10 in the adjacent wall of the case 1 and made axially hollow at 11 to receive the outer end of the screw 7, which for convenience is grooved at A12 and splined or held by a tongue 13 to the nut. By this simple means the u'ser of the receiver can instantly and at any moment regulate the flux through the cores of the electromagnets at their terminals next to the diaphragm simply by turning the nut 11 one way or the other so as to bring the screw 7 (which constitutes a vinculum or conductor of the lines of force) nearer or farther from the opposite core 4. When this soft iron conductor 7 contacts with the core 4 it forms a practically closed magnetic circuit and hence cuts `down the effective lines of force to a minimum, and by moving the magnetic conductor 7 back away from the core 4 more and more lines of force are permitted'to influence and to be influenced by the dia-` phragm. This accomplishes theV desired regulation of the audiphone receiver without varying the current in the windings. The conductor 7 is really a magnetic shunt for switching oif or drawing away an amount of flux from the magnetic field determined by the space between the front end of the screw or other form of Slide 7 and the adjacent core.

In Figs. 4 and 5 I have shown another form of my invention, in which a plate or block 14 is arranged to slide longitudinally in a recess or slot 15 provided through the adjacent core 5, being operated'by a screw 15 threaded into said block 14 and having its head 17 projecting externally for convenience in operating the magnetic switch or regulator 14.

In- Figs. 6 and 7 I have shown the flux controller or means for regulating the eective linesof force, in the form of a soft iron plate 18 guided between two opposite guides 19 of non-magnetic material and moved bodily in parallelism tolitself by a screw-20 ros y llt swiveled at 2l centrally in the back of the case so that by advancing or retarding the plate 18 the gap between said plate and the adjacent cores 4 and 5 is varied, thereby correspondingly varying the flux substantially in the same manner as more fully described above. It is always desirable that the magnetic regulator shall have as much or more cross-sectional area as the electromagnet pole or core.

l prefer the screw embodiment of the invention, as it is desirable to have one of the screws connected to the regulating device Without an air space, as it is Well known that an air space kills the efficiency of magnetism, but at the same time li Wish it understood that l am not restricted to this embodiment or to any of the specific embodiments of my invention herein shown as the movement of the regulating device need not be even a sliding movement, the idea being simpl)r to provide a variable magnetic path for regulating the iiuX, and as long as means for accomplishing this purpose is provided l consider it Within the spirit and scope oi' my invention.

Having described my invention, what l claim as new and desire to secure by Letters iatent, is, J

l. An audiphone receiver, having an electromagnet and a diaphragm, combined vvith magnetic means for establishing a shunt path in the magnetic field for the lines of force of said electromagnet, and means for moving said magnetic means transversely of the electromagnet.

2. An audiphone receiver, having an electromagnet, a coperating diaphragm, a soft iron conductor adjacent the cores of the magnet, and external operating means to move said conductor toward and from said cores.

3. An audiphone receiver, having an electromagnet, a cooperating diaphragm, a soft iron screw threaded through one core of the electromagnet, and means for advancing said screw tovvard and from the other core of the electromagnet.

4. An audiphone receiver, having an electromagnet, a coperating diaphragm, a soft iron magnetic conductor movably mounted in contact with one of the cores of said mag net adjacent the under side of said diaphragm, and external means for moving said conductor toward and from the other core oit' the electromagnet.

in testimony whereof, l have signed my name to this specification, in the presence of two subscribing Witnesses.

CHARLES E. WILLAMS.

Witnessesz M. J. SPALDING, WILLIAM J. PIKE. 

